Lyxose is an aldopentose — a monosaccharide containing five carbon atoms, and including an aldehyde functional group.
It has chemical formula C5H10O5.
It is a C'-2 carbon epimer of the sugar xylose.
The name "lyxose" comes from reversing the prefix "xyl" in "xylose".
Lyxose occurs only rarely in nature, for example, as a component of bacterial glycolipids.